The Trump administration launched a wide-ranging probe of aluminum imports that could end in broad tariffs or other trade restrictions on the metal, The Wall Street Journal reports. Producers in Canada and China – by far the biggest aluminum exporters to the US – could face the biggest impact from any tariffs coming out of the case, which may raise US domestic aluminum prices. The new administration is increasingly relying on national security as an argument for considering tariffs or other tools that could block some imports and help rebuild parts of American industry. The aluminum case follows a steel inquiry that the Commerce Department launched this month. Both cases will likely give the Trump administration leverage in resolving what US metal producers see as global overcapacity, in large part caused by Chinese production.